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                                                                     EXHIBIT 4.2


               AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT


         THIS AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT (this
"AGREEMENT") is made as of June 16, 2004 by and among Crdentia Corp., a Delaware
corporation (the "COMPANY") and MedCap Partners L.P. ("MEDCAP").


                                    RECITALS:
                                    ---------

         A. The Company and MedCap are parties to that certain Registration
Rights Agreement dated December 16, 2003 (the "ORIGINAL AGREEMENT").

         B. The Company and MedCap are parties to that certain Subscription
Agreement (the "SUBSCRIPTION AGREEMENT"), dated June 16, 2004, regarding the
proposed sale and issuance of shares of the Company's Series B Preferred Stock
(the "SERIES B PREFERRED") to MedCap (the "PREFERRED STOCK FINANCING");

         C. The Original Agreement may be amended by a written agreement
executed by the Company and the holders of sixty-six and two-thirds percent (66
2/3%) of the securities registrable under the Original Agreement.

         D. MedCap holds more than sixty-six and two-thirds percent (66 2/3%) of
the securities registrable under the Original Agreement

         E. In connection with the Preferred Stock Financing, the Company and
MedCap desire to agree to the terms and conditions set forth herein, and to
amend, restate and supercede the Original Agreement.


                                    AGREEMENT
                                    ---------

         NOW, THEREFORE, in consideration of the mutual promises,
representations, warranties, covenants and conditions set forth in this
Agreement and the Subscription Agreement, the parties hereto agree as follows:

         1. REGISTRATION RIGHTS. The Company covenants and agrees as follows:

             1.1 DEFINITIONS. For purposes of this Agreement:

                  (a) The term "ACT" means the Securities Act of 1933, as
amended.

                  (b) The term "FORM S-3" means such form under the Act as in
effect on the date hereof or any registration form under the Act subsequently
adopted by the SEC which permits inclusion or incorporation of substantial
information by reference to other documents filed by the Company with the SEC.

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                  (c) The term "HOLDER" means any person owning or having the
right to acquire Registrable Securities or any assignee thereof in accordance
with SECTION 1.11 hereof.

                  (d) The term "1934 ACT" shall mean the Securities Exchange Act
of 1934, as amended.

                  (e) The term "REGISTER," "REGISTERED," and "REGISTRATION"
refer to a registration effected by preparing and filing a registration
statement or similar document in compliance with the Act, and the declaration or
ordering of effectiveness of such registration statement or document.

                  (f) The term "REGISTRABLE SECURITIES" means (i) the Common
Stock of the Company (the "COMMON STOCK") issued to the Investors listed on
SCHEDULE A attached hereto pursuant to conversion of the Series B Preferred
and/or the Series A Preferred Stock of the Company, as the case may be, and (ii)
any Common Stock issued as (or issuable upon the conversion or exercise of any
warrant, right or other security which is issued as) a dividend or other
distribution with respect to, or in exchange for or in replacement of the shares
referenced in (i) above, excluding in all cases, however, any Registrable
Securities sold by a person in a transaction in which his rights under this
SECTION 1 are not assigned pursuant to the terms of this Agreement.

                  (g) The number of shares of "REGISTRABLE SECURITIES THEN
OUTSTANDING" shall be determined by the number of shares of Common Stock
outstanding which are, and the number of shares of Common Stock issuable
pursuant to then exercisable or convertible securities which are, Registrable
Securities.

                  (h) The term "SEC" shall mean the Securities and Exchange
Commission.

             1.2 REQUESTED REGISTRATION.

                  (a) REQUEST FOR REGISTRATION. If, at any time after July 1,
2004, the Company shall receive from the Holders of thirty-three and one-third
percent (33 1/3%) or more of the Registrable Securities then outstanding (the
"INITIATING HOLDERS") a written request that the Company file a registration
statement in accordance with the Act covering the registration on a continuous
basis pursuant to Rule 415 under the Act, or any successor rule or regulation
("RULE 415") of all or part of the Registrable Securities then held by such
Holders, the Company shall:

                       (i) within ten (10) days of the receipt thereof, give
written notice of the proposed registration, qualification or compliance to all
other Holders; and

                       (ii) within forty-five (45) days of the receipt thereof,
file a registration statement with the SEC and use its reasonable and diligent
efforts to effect as soon as practicable, the registration under the Act of all
such Holders' Registrable Securities as are specified in such request, together
with such portion of the Registrable Securities of any other Holder or Holders
joining in such request as are specified in a written notice given within
fifteen (15) days after receipt of written notice from the Company; PROVIDED,
HOWEVER, that the Company shall not be obligated to take any action to effect
any such registration pursuant to this SECTION 1.2, (A) after the Company has
effected one (1) registration under this SECTION 1.2 or (B) if less than
thirty-three and one-third percent (33 1/3%) of the then outstanding Registrable
Securities will be registered.


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                  (b) REGISTRATION STATEMENTS. Any registration statement filed
pursuant to this SECTION 1.2 shall be on Form S-3, or if Form S-3 is not
available, Form S-1 or other appropriate form permitting registration of the
Registrable Securities for resale by the Holders.

                  (c) UNDERWRITING. If the Holders at any time intend to
distribute all or a part of the Registrable Securities covered by the
registration statement filed pursuant to this SECTION 1.2 by means of an
underwriting, they shall so advise the Company and the Company shall promptly
notify the other Holders of such underwriting. The Company (together with all
Holders proposing to distribute their securities pursuant to the underwriting)
shall enter into an underwriting agreement in customary form with the
underwriter or underwriters selected by the Company. Notwithstanding any other
provision of this SECTION 1.2, if the underwriter advises the Holders in writing
that marketing factors require a limitation of the number of shares to be
underwritten, then the Holders requesting the underwriting shall so advise all
Holders of Registrable Securities, and the number of shares included in the
underwriting shall be allocated among the Holders of Registrable Securities
requesting registration in proportion, as nearly as practicable, to the total
number of Registrable Securities held by such Holders at the time of the request
for an underwriting. If any Holder disapproves of the terms of the underwriting,
such Holder may elect to withdraw from such underwritten offering by written
notice to the Company, the underwriter and the other Holders whose shares are
being included in the underwriting. The Company agrees to file any amendments or
supplements to the registration statement necessary in order to permit any
underwritten offering.

                  (d) RIGHTS IN ADDITION TO OTHER RIGHTS. The rights under this
SECTION 1.2 are in addition to, and not affected by, the Holders' exercise of
any registration rights contained in SECTION 1.3.

              1.3 COMPANY REGISTRATION. If (but without any obligation to do so)
the Company proposes to register any of its stock or other securities under the
Act in connection with the public offering of such securities solely for cash
(other than a registration relating solely to the sale of securities to
participants in a Company employee benefit plan or corporate reorganization or
other transaction covered by Rule 145 promulgated under the Act, or a
registration on any form which does not permit secondary sales or include
substantially the same information as would be required to be included in a
registration statement covering the sale of the Registrable Securities), the
Company shall, at such time, promptly give each Holder written notice of such
registration. Upon the written request of each Holder given within twenty (20)
days after mailing of such notice by the Company in accordance with SECTION 2.6
hereof, the Company shall, subject to the provisions of SECTION 1.7 hereof,
cause to be registered under the Act all of the Registrable Securities that each
such Holder has requested to be registered.


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              1.4 OBLIGATIONS OF THE COMPANY. Whenever required under this
SECTION 1 to effect the registration of any Registrable Securities, the Company
shall, as expeditiously as reasonably possible:

                  (a) Prepare and file with the SEC a registration statement
with respect to such Registrable Securities and use its reasonable and diligent
efforts to cause such registration statement to become effective, and keep such
registration statement effective (i) in the case of a registration statement
filed pursuant to SECTION 1.2, during the Effectiveness Period (as hereinafter
defined) or (ii) in the case of a registration statement filed pursuant to
SECTION 1.3, upon the request of the Holders of a majority of the Registrable
Securities registered thereunder, for up to three hundred sixty-five (365) days
or, if earlier, the date on which the distribution contemplated in the
registration statement has been completed. As used herein, the term
"EFFECTIVENESS PERIOD" shall mean until the earlier of (i) the termination of
the rights set forth in this Agreement in accordance with Section 1.14 or (ii)
all of the Registrable Securities covered by the registration having been sold
or a subsequent registration statement covering any unsold Registrable
Securities having been declared effective.

                  (b) Provide, at least three (3) business days prior to filing,
any registration statement and included prospectus (including each preliminary
prospectus and any amendments or supplements thereto) prepared in conformity
with the requirements of the Act in connection with SECTIONS 1.2 and 1.3 (the
"REGISTRATION Materials") to the Holders and their respective counsel for review
and comment, if any.

                  (c) Prepare and file with the SEC such amendments and
supplements to such registration statement and the prospectus used in connection
with such registration statement as may be necessary to comply with the
provisions of the Act with respect to the disposition of all securities covered
by such registration statement.

                  (d) Furnish to the Holders such number of copies of a
prospectus, including a preliminary prospectus, in conformity with the
requirements of the Act, and such other documents and Registration Materials as
they may reasonably request in order to facilitate the disposition of
Registrable Securities owned by them that are included in such registration.

                  (e) Use its reasonable and diligent efforts to register and
qualify the securities covered by such registration statement under such other
securities or Blue Sky laws of such jurisdictions as shall be reasonably
requested by the Holders; PROVIDED, HOWEVER, that the Company shall not be
required in connection therewith or as a condition thereto to qualify to do
business or to file a general consent to service of process in any such states
or jurisdictions.

                  (f) In the event of any underwritten public offering, enter
into and perform its obligations under an underwriting agreement, in usual and
customary form, with the managing underwriter of such offering. Each Holder
participating in such underwriting shall also enter into and perform its
obligations under such agreement.

                  (g) Notify each Holder of Registrable Securities covered by
such registration statement at any time when a prospectus relating thereto is
required to be delivered under the Act of the happening of any event the result
of which causes the prospectus included in such registration statement, as then
in effect, to include an untrue statement of a material fact or omit to state a
material fact required to be stated therein or necessary to make the statements

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therein not misleading in light of the circumstances then existing; and
thereafter, the Company will use reasonable efforts to amend or supplement such
prospectus in order to cause such prospectus not to include any untrue statement
of a material fact or omit to state a material fact required to be stated
therein or necessary to make the statements therein not misleading in light of
circumstances then existing; PROVIDED, HOWEVER, that upon such notification by
the Company, the Holders will not offer or sell Registrable Securities until the
Company has notified the Holders that it has prepared a supplement or amendment
to such prospectus and delivered copies of such supplement or amendment to the
Holders (it being understood and agreed by the Company that the foregoing
proviso shall in no way diminish or otherwise impair the Company's obligations
to prepare a prospectus amendment or supplement as above provided in this
SECTION 1.4(G)).

                  (h) Use its reasonable and diligent efforts, if a registration
statement under SECTION 1.2 ceases to be effective for any reason at any time
during the Effectiveness Period (other than because of the sale of all of the
Registrable Securities registered thereunder or pursuant to the Company's
exercise of the Suspension Right (as hereinafter defined)), to (i) obtain the
prompt withdrawal of any order suspending the effectiveness thereof, and (ii)
amend the registration statement in a manner reasonably expected to obtain the
withdrawal of the order suspending the effectiveness of the shelf registration
or file an additional registration statement covering all of the unsold
Registrable Securities (a "Subsequent Registration Statement"). If a Subsequent
Registration Statement is filed, the Company will use its reasonable and
diligent efforts to cause the Subsequent Registration Statement to be declared
effective as soon as practicable and to keep such Subsequent Registration
Statement continuously effective until the end of the Effectiveness Period. The
requirements of this SECTION 1.4(H) that the Company file additional
registration statements shall not be affected by the provisions set forth in
SECTION 1.2 that the Company is only required to file one registration statement
under SECTION 1.2.

                  (i) Cause all such Registrable Securities registered pursuant
hereunder to be listed on each securities exchange on which similar securities
issued by the Company are then listed.

                  (j) Provide a transfer agent and registrar for all Registrable
Securities registered pursuant hereunder and a CUSIP number for all such
Registrable Securities, in each case not later than the effective date of such
registration.

                  (k) Use its reasonable and diligent efforts to furnish, at the
request of any Holder requesting registration of Registrable Securities pursuant
to this SECTION 1, on the date that such Registrable Securities are delivered to
the underwriters for sale in connection with a registration statement pursuant
to this SECTION 1, if such securities are being sold through underwriters, or,
if such securities are not being sold through underwriters, on the date that the
registration statement with respect to such securities becomes effective, (i) an
opinion, dated such date, of the counsel representing the Company for the
purposes of such registration, in form and substance as is customarily given to
underwriters in an underwritten public offering, addressed to the underwriters,
if any, and to the Holders requesting registration of the Registrable
Securities, and (ii) a letter dated such date, from the independent certified
public accountants of the Company, in form and substance as is customarily given
by independent certified public accountants to underwriters in an underwritten
public offering, addressed to the underwriters, if any, and to the Holders
requesting registration of Registrable Securities.


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                  (l) Notify each seller of Registrable Securities under such
registration statement of (i) the effectiveness of such registration statement,
(ii) the filing of any post-effective amendments to such registration statement,
or (iii) the filing of a supplement to such registration statement.

             1.5 FURNISH INFORMATION.

                  (a) It shall be a condition precedent to the obligations of
the Company to take any action pursuant to this SECTION 1 with respect to the
Registrable Securities of any selling Holder that such Holder shall furnish to
the Company such information regarding itself, the Registrable Securities held
by it, and the intended method of disposition of such securities as shall be
required to effect the registration of such Holder's Registrable Securities.

                  (b) The Company shall have no obligation with respect to any
registration requested pursuant to SECTION 1.2 hereof if, as a result of the
application of subsection 1.5(a), the number of shares of the Registrable
Securities to be included in the registration does not equal or exceed the
number of shares required to originally trigger the Company's obligation to
initiate such registration as specified in SECTION 1.2 hereof.

              1.6 EXPENSES OF REGISTRATION. All expenses (other than
underwriting discounts and commissions, stock transfer taxes and fees of counsel
to the stockholders in excess of $15,000) incurred in connection with any
registrations, filings or qualifications of Registrable Securities pursuant to
SECTIONS 1.2 or 1.3 including (without limitation) all federal or state
registration, filing and qualification fees, printers' and accounting fees and
fees and disbursements of counsel for the Company shall be borne by the Company.
The Company shall pay up to an aggregate of $15,000 of the selling stockholders'
legal fees in connection with one (1) registration. Notwithstanding the
foregoing, the Company shall not be required to pay for any expenses of any
registration proceeding begun pursuant to SECTION 1.2 if the registration
request is subsequently withdrawn at the request of the Holders of a majority of
the Registrable Securities to be registered, unless the withdrawal is based upon
a material adverse development concerning the Company and the Holders have
withdrawn the request with reasonable promptness following disclosure by the
Company of such material adverse change.

              1.7 UNDERWRITING REQUIREMENTS. In connection with any offering
pursuant to SECTION 1.3 involving an underwriting of shares of the Company's
capital stock by the Company, the Company shall not be required to include any
of the Holders' securities in such underwriting unless they accept the terms of
the underwriting as agreed upon between the Company and the underwriters
selected by it (or by other persons entitled to select the underwriters), and
then only in such quantity as the underwriters determine in their sole
discretion will not jeopardize the success of the offering by the Company. If
the total amount of securities, including Registrable Securities, requested by
stockholders to be included in such offering exceeds the amount of securities
sold other than by the Company that the underwriters determine in their sole
discretion is compatible with the success of the offering, then the Company
shall be required to include in the offering only that number of such


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securities, including Registrable Securities, which the underwriters determine
in their sole discretion will not jeopardize the success of the offering (the
securities so included to be apportioned pro rata among the selling stockholders
according to the total amount of securities entitled to be included therein
owned by each selling stockholder, or in such other proportions as shall
mutually be agreed to by such selling stockholders). For purposes of the
preceding parenthetical concerning apportionment, for any selling stockholder
which is a holder of Registrable Securities and which is a limited liability
company, partnership or corporation, the members, partners, retired partners and
stockholders of such holder, or the estates and family members of any such
members, partners and retired partners and any trusts for the benefit of any of
the foregoing persons shall be deemed to be a single "selling stockholder," and
any pro-rata reduction with respect to such "selling stockholder" shall be based
upon the aggregate amount of shares carrying registration rights owned by all
entities and individuals included in such "selling stockholder," as defined in
this sentence.

              1.8 DELAY OF REGISTRATION. No Holder shall have any right to
obtain or seek an injunction restraining or otherwise delaying any such
registration as the result of any controversy that might arise with respect to
the interpretation or implementation of this SECTION 1.

              1.9 INDEMNIFICATION. In the event any Registrable Securities are
included in a registration statement under this SECTION 1:

                  (a) To the maximum extent permitted by law, the Company will
indemnify and hold harmless each Holder, the partners, officers, and directors
of each Holder, any underwriter (as defined in the Act) for such Holder and each
person, if any, who controls such Holder or underwriter within the meaning of
the Act or the 1934 Act, against any losses, claims, damages or liabilities
(joint or several) to which they may become subject under the Act, the 1934 Act
or any state securities law, insofar as such losses, claims, damages or
liabilities (or actions in respect thereof) arise out of or are based upon any
of the following statements, omissions or violations (collectively a
"VIOLATION"): (i) any untrue statement or alleged untrue statement of a material
fact contained in such registration statement, including any preliminary
prospectus or final prospectus contained therein or any amendments or
supplements thereto, (ii) the omission or alleged omission to state therein a
material fact required to be stated therein, or necessary to make the statements
therein not misleading, or (iii) any violation or alleged violation by the
Company of the Act, the 1934 Act, or any rule or regulation promulgated under
the Act or the 1934 Act or any state securities law in connection with the
offering covered by such Registration Statement; and the Company will pay to
each such Holder, partner, officer, director, underwriter or controlling person,
as incurred, any legal or other expenses reasonably incurred by them in
connection with investigating or defending any such loss, claim, damage,
liability or action; PROVIDED, HOWEVER, that the indemnity agreement contained
in this subsection 1.9(a) shall not apply to amounts paid in settlement of any
such loss, claim, damage, liability, or action if such settlement is effected
without the consent of the Company (which consent shall not be unreasonably
withheld or delayed), nor shall the Company be liable to any Holder, underwriter
or controlling person for any such loss, claim, damage, liability or action to
the extent that it arises out of or is based upon a Violation which occurs in
reliance upon and in conformity with written information furnished expressly for
use in connection with such registration by any such Holder, partner, officer,
director, underwriter or controlling person.


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                  (b) To the maximum extent permitted by law, each selling
Holder will, if Registrable Securities held by such Holder are included in the
applicable registration statement, indemnify and hold harmless the Company, each
of its directors, each of its officers who has signed the registration
statement, each person, if any, who controls the Company within the meaning of
the Act, any underwriter, any other Holder selling securities in such
registration statement and any controlling person of any such underwriter or
other Holder, against any losses, claims, damages or liabilities (joint or
several) to which any of the foregoing persons may become subject under the Act
or the 1934 Act or any state securities law in connection with the offering
covered by such registration statement insofar as such losses, claims, damages
or liabilities (or actions in respect thereto) arise out of or are based upon
any Violation, in each case to the extent (and only to the extent) that such
Violation occurs in reliance upon and in conformity with written information
furnished by such Holder expressly for use in connection with such registration;
and each such Holder will pay any legal or other expenses reasonably incurred by
any person intended to be indemnified pursuant to this subsection 1.9(b), in
connection with investigating or defending any such loss, claim, damage,
liability or action; PROVIDED, HOWEVER, that the indemnity agreement contained
in this subsection 1.9(b) shall not apply to amounts paid in settlement of any
such loss, claim, damage, liability or action if such settlement is effected
without the consent of the Holder (which consent shall not be unreasonably
withheld or delayed); PROVIDED FURTHER, that in no event shall any indemnity
under this subsection 1.9(b) exceed the net proceeds from the offering received
by such Holder, except in the case of willful misconduct or fraud by such
Holder.

                  (c) Promptly after receipt by an indemnified party under this
SECTION 1.9 of notice of the commencement of any action (including any
governmental action) as to which indemnity may be sought hereunder, such
indemnified party will, if a claim in respect thereof is to be made against any
indemnifying party under this SECTION 1.9, deliver to the indemnifying party a
written notice of the commencement thereof. The indemnifying party shall have
the right to participate in, and, to the extent the indemnifying party so
desires, jointly with any other indemnifying party similarly noticed, to assume
the defense thereof with counsel mutually satisfactory to the parties; PROVIDED,
HOWEVER, that an indemnified party (together with all other indemnified parties
which may be represented without conflict by one counsel) shall have the right
to retain one separate counsel, with the reasonable fees and expenses to be paid
by the indemnifying party, if representation of such indemnified party by the
counsel retained by the indemnifying party would be inappropriate due to actual
or potential differing interests between such indemnified party and any other
party represented by such counsel in such proceeding. The failure to deliver
written notice to the indemnifying party within a reasonable time of the
commencement of any such action, if prejudicial to its ability to defend such
action, shall relieve such indemnifying party of any liability to the
indemnified party under this SECTION 1.9, but the omission to so deliver written
notice to the indemnifying party will not relieve the indemnifying party of any
liability that it may have to any indemnified party otherwise than under this
SECTION 1.9. No indemnifying party, in the defense of any such claim or
litigation, shall, except upon the consent of each indemnified party, consent to
entry of any judgment or enter into any settlement that does not include as an
unconditional term thereof the giving by the claimant or plaintiff to such
indemnified party of a full and unconditional release from all liability in
respect to such claim or litigation.


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                  (d) The foregoing indemnity agreements of the Company and
Holders are subject to the condition that, insofar as they related to any
Violation made in a preliminary prospectus but eliminated or remedied in the
amended prospectus on file with the SEC at the time the registration statement
in question becomes effective or the amended prospectus filed with the SEC
pursuant to SEC Rule 424(b) (the "FINAL PROSPECTUS"), such indemnity agreement
shall not inure to the benefit of any person if a copy of the Final Prospectus
was furnished to the indemnified party and was not furnished to the person
asserting the loss, liability, claim or damage at or prior to the time such
action is required by the Act. If the indemnification provided for in this
SECTION 1.9 is held by a court of competent jurisdiction to be unavailable to an
indemnified party with respect to any loss, claim, damage or liability referred
to herein, then the indemnifying party, in lieu of indemnifying such indemnified
party hereunder, shall contribute to the amount paid or payable by such
indemnified party as a result of such loss, claim, damage or liability in such
proportion as is appropriate to reflect the relative fault of the indemnifying
party on the one hand and of the indemnified party on the other in connection
with the statements or omissions that resulted in such loss, claim, damage or
liability, as well as any other relevant equitable considerations; PROVIDED,
HOWEVER, that in no event shall (i) any contribution by a Holder under this
subsection 1.9(d) exceed the net proceeds from the offering received by such
Holder, except in the case of willful fraud by such Holder, and (ii) any person
or entity guilty of fraudulent misrepresentation (within the meaning of Section
11(f) of the Act) be entitled to contribution from any person or entity who was
not guilty of such fraudulent misrepresentation. The relative fault of the
indemnifying party and of the indemnified party shall be determined by reference
to, among other things, whether the untrue or alleged untrue statement of a
material fact or the omission to state a material fact relates to information
supplied by the indemnifying party or by the indemnified party and the parties'
relative intent, knowledge, access to information and opportunity to correct or
prevent such statement or omission.

                  (e) Notwithstanding the foregoing, to the extent that the
provisions on indemnification and contribution contained in the underwriting
agreement entered into in connection with the underwritten public offering are
in conflict with the foregoing provisions, the provisions in the underwriting
agreement shall control.

                  (f) The obligations of the Company and Holders under this
SECTION 1.9 shall survive the completion of any offering of Registrable
Securities in a registration statement under this SECTION 1, and otherwise.

              1.10 ASSIGNMENT OF REGISTRATION RIGHTS. The rights to cause the
Company to register Registrable Securities pursuant to this Section 1 may be
assigned (but only with all related obligations) by a Holder to a transferee or
assignee of such securities, including a subsidiary, affiliate, partner, limited
partner, retired partner or stockholder of a Holder, provided in each case that
(i) the Company is, within a reasonable time after such transfer, furnished with
written notice of the name and address of such transferee or assignee and the
securities with respect to which such registration rights are being assigned;
(ii) such transferee or assignee agrees in writing to be bound by and subject to
the terms and conditions of this Agreement; and (iii) such assignment shall be
effective only if immediately following such transfer the further disposition of
such securities by the transferee or assignee is restricted under the Act.


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              1.11 REPORTS UNDER THE 1934 ACT. The Company agrees to use
commercially reasonable efforts: (a) to make and keep public information
available, as those terms are understood and defined in the General Instructions
to Form S-3, or any successor or substitute form, and in Rule 144, (b) to file
with the SEC in a timely manner all reports and other documents required to be
filed by an issuer of securities registered under the Securities Act or the
Exchange Act, (c) as long as any Holder owns any Registrable Securities, to
furnish in writing upon such Holder's request a written statement by the Company
that it has complied with the reporting requirements of Rule 144 and of the Act
and the 1934 Act, and to furnish to such Holder a copy of the most recent annual
or quarterly report of the Company, and such other reports and documents so
filed by the Company with the SEC as may be reasonably requested.

              1.12 DEFERRAL. Notwithstanding anything in this Agreement to the
contrary, if the Company shall furnish to the Holders a certificate signed by
the Chief Executive Officer of the Company stating that the Board of Directors
of the Company has made the good faith determination (a) that continued use by
the Holders of a registration statement for purposes of effecting offers or
sales of Registrable Securities pursuant thereto would require, under the Act,
premature disclosure in the registration statement (or the prospectus relating
thereto) of material, nonpublic information concerning the Company, its business
or prospects or any proposed material transaction involving the Company, (b)
that such premature disclosure would be materially adverse to the Company, its
business or prospects or any such proposed material transaction or would make
the successful consummation by the Company of any such material transaction
significantly less likely and (c) that it is therefore essential to suspend the
use by the Holders of any such registration statement (and the prospectus
relating thereto) for purposes of effecting offers or sales of Registrable
Securities pursuant thereto, then the right of the Holders to use any such
registration statement (and the prospectus relating thereto) for purposes of
effecting offers or sales of Registrable Securities pursuant thereto shall be
suspended until further notice by the Company (the "SUSPENSION PERIOD"). During
the Suspension Period, none of the Holders shall offer or sell any Registrable
Securities pursuant to or in reliance upon any such registration statement (or
the prospectus relating thereto). In the event the Company exercises the
suspension rights set forth herein (the "SUSPENSION RIGHT"), such suspension
will continue for such period of time reasonably necessary for disclosure to
occur at a time that is not materially detrimental to the Company or until such
time as the registration statement does not include any untrue statement of a
material fact or omit to state any material fact required to be stated therein
or necessary to make the statements therein not misleading in light of the
circumstances under which they were made, each as determined in good faith by
the Company. The Company agrees to notify the Holders promptly upon termination
of the Suspension Right. Notwithstanding the foregoing, under no circumstances
shall the Company be entitled to exercise the Suspension Right for a period of
more than thirty (30) days during any twelve (12) month period.

              1.13 LIMITATION OF LIABILITY. The Company shall not be liable to
the Holder for a failure to effect, or a delay in effecting, a registration
hereunder or a default in any other obligations under this Agreement arising out
of or relating to any failure to receive necessary consents from its independent
auditors or any internal review, investigation or similar activity by the
Company's Audit Committee.


                                      -10-
<PAGE>

              1.14 TERMINATION OF REGISTRATION RIGHTS. The rights granted under
this Section 1 shall terminate upon the fourth anniversary of the date of this
Agreement. In addition, a Holder's registration rights shall terminate if all
Registrable Securities held by and issuable to such Holder may be sold under
Rule 144 during any ninety (90) day period.

         2. MISCELLANEOUS.

              2.1 SUCCESSORS AND ASSIGNS. Except as otherwise provided herein,
the terms and conditions of this Agreement shall inure to the benefit of and be
binding upon the respective successors and assigns of the parties (including
transferees of any shares of Registrable Securities). Nothing in this Agreement,
express or implied, is intended to confer upon any party other than the parties
hereto or their respective successors and assigns any rights, remedies,
obligations, or liabilities under or by reason of this Agreement, except as
expressly provided in this Agreement.

              2.2 GOVERNING LAW. This Agreement shall be governed by and
construed under the laws of the State of Delaware as applied to agreements among
Delaware residents entered into and to be performed entirely within Delaware.

              2.3 SUBMISSION TO JURISDICTION; WAIVERS. Each of the parties
hereto irrevocably agrees that any legal action or proceeding with respect to
this Agreement or for the recognition and enforcement of any judgment in respect
hereof brought by the other party hereto or its successors or assigns will be
brought and determined in the Chancery or other courts of the State of Delaware,
and each of the parties hereby irrevocably submits with regard to any such
action or proceeding for itself and in respect to its property, generally and
unconditionally, to the exclusive jurisdiction of the aforesaid courts. Each of
the parties hereto hereby irrevocably waives, and agrees not to assert, by way
of motion, as a defense, counterclaim or otherwise, in any action or proceeding
with respect to this Agreement, (a) any claim that it is not personally subject
to the jurisdiction of the above-named courts for any reason other than the
failure to lawfully serve process, (b) that it or its property is exempt or
immune from jurisdiction of any such court or from any legal process commenced
in such courts (whether through service of notice, attachment prior to judgment,
attachment in aid of execution of judgment, execution of judgment or otherwise),
(c) to the fullest extent permitted by applicable law, that (i) the suit, action
or proceeding in any such court is brought in an inconvenient forum, (ii) the
venue of such suit, action, or proceeding is improper and (iii) this Agreement,
or the subject matter hereof, may not be enforced in or by such courts and (d)
any right to trial by jury.

              2.4 COUNTERPARTS. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

              2.5 TITLES AND SUBTITLES. The titles and subtitles used in this
Agreement are used for convenience only and are not to be considered in
construing or interpreting this Agreement.


                                      -11-
<PAGE>

              2.6 NOTICES. All notices and other communications required or
permitted hereunder shall be in writing and shall be deemed effectively given:
(a) upon personal delivery to the party to be notified, (b) when sent by
confirmed facsimile if sent during normal business hours of the recipient or, if
not sent during normal business hours, then on the next business day, (c) three
days after having been sent by registered or certified mail, return receipt
requested, postage prepaid, or (d) one day after deposit with a nationally
recognized overnight courier, specifying next day delivery, with written
verification of receipt. All communications shall be sent to the address as set
forth on the signature page hereof or at such other address as such party may
designate by 10 days advance written notice to the other parties hereto.

              2.7 EXPENSES. If any action at law or in equity is necessary to
enforce or interpret the terms of this Agreement, the prevailing party shall be
entitled to reasonable attorneys' fees, costs and necessary disbursements in
addition to any other relief to which such party may be entitled.

              2.8 AMENDMENTS AND WAIVERS. Any term of this Agreement may be
amended and the observance of any term of this Agreement may be waived (either
generally or in a particular instance and either retroactively or
prospectively), only with the written consent of the Company and the Holders of
sixty-six and two-thirds percent (66 2/3%) of the Registrable Securities then
outstanding. Any amendment or waiver effected in accordance with this paragraph
shall be binding upon each Holder of any Registrable Securities then
outstanding, each future Holder of all such Registrable Securities, and the
Company.

              2.9 SEVERABILITY. If one or more provisions of this Agreement are
held to be unenforceable under applicable law, such provision shall be excluded
from this Agreement and the balance of the Agreement shall be interpreted as if
such provision were so excluded and shall be enforceable in accordance with its
terms.

              2.10 AGGREGATION OF STOCK. All shares of Registrable Securities
held or acquired by affiliated entities or persons shall be aggregated together
for the purpose of determining the availability of any rights under this
Agreement.

              2.11 ENTIRE AGREEMENT; AMENDMENT; WAIVER. This Agreement
(including Schedule A hereto) constitutes the full and entire understanding and
agreement between the parties with regard to the subjects hereof and thereof.



                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]




                                      -12-
<PAGE>


         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first above written.


                                    CRDENTIA CORP.,
                                    a Delaware corporation


                                    By: /S/ JAMES D. DURHAM
                                        -----------------------------------
                                    Name:    James D. Durham
                                    Title:   Chief Executive Officer

                                    Address: 14114 Dallas Parkway, Suite 600
                                             Dallas, Texas  75254


<PAGE>


         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first above written.

                                    MEDCAP:

                                    MEDCAP PARTNERS L.P.

                                    BY:  MEDCAP MANAGEMENT & RESEARCH LLC
                                    ITS:  GENERAL PARTNER


                                    By: /S/ C. FRED TONEY
                                        ------------------------------------
                                    Name:    C. Fred Toney
                                    Title:   Managing Member

                                    Address:    500 Third Street, Suite 535
                                                San Francisco, California  94107

<PAGE>



                                   SCHEDULE A
                                   ----------

                              SCHEDULE OF INVESTORS

MedCap Partners L.P.
SF Capital Partners, Ltd.